For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningHill and Mountain Roads
Driving on steep hills or through mountains is different than driving on flat
or rolling terrain. Tips for driving in these conditions include:
• Keep the vehicle serviced and in good shape.
• Check all fluid levels and brakes, tires, cooling system, and transmission.
• Shift to a lower g ...
Installation Procedure
Clean and prepare the attaching surfaces for welding.
Position the roof rear header panel (1) on the vehicle.
Verify the fit of the panel.
Clamp the roof rear header panel into position.
Spot weld accordingly as noted from the original panel.
Apply the sealer ...
Lamp Messages
AUTOMATIC LIGHT CONTROL ON
This message is displayed when the automatic light control has been turned on.
AUTOMATIC LIGHT CONTROL OFF
This message is displayed when the automatic light control has been turned off.
XXX TURN INDICATOR FAILURE
When one of the turn signals is out, this message disp ...